1. Operation of the Aerodynamic Plasma Actuator at High Altitude Timothy Nichols and Joshua Rovey Department of Mechanical and Aerospace Engineering Missouri University of Science & Technology Presented to: Thesis Committee April 24 th, 2012

2. Outline I.Background II.Research Approach III.Results IV.Conclusion 2

3. Background Effects of low pressure environment on actuators: Large extension of plasma region Power consumption increases Force and effectiveness decrease 3

4. Background 4 Force production depends on number of ions and electric field More power going into creating plasma instead of accelerating it?

5. Research Approach Spatiotemporal evolution of the surface potential and electric field found using capacitive probes Experimentally determine why force decreases Does calculated average force agree with experimentally determined force in literature? 5

6. V-Dot Probes 6

7. 7

8. 8

9. 9

10. Results 10

11. Results 760 Torr 88 Torr 11

12. Results 760 Torr 88 Torr 12

13. Results 13

14. Current Progress 14

15. Results 15

16. Results 16

17. Results 17

18. Results 18

19. Conclusions Peak physical charge deposition corresponds closely with peak surface potential Electric field remains largely unchanged close to the exposed electrode edge Surface potential is spread across surface E-Field is zero for approximately 80% of surface at lower pressures compared to 55% at 760 Torr 20 times more plasma created at lower pressures than at atmospheric conditions 88% of this plasma in region with E = 0 More power into creating plasma than accelerating it 19

20. Questions 20

21. Back-up Slides 21

22. Back-up Slides 22

23. Back-up Slides 23